Field of the Invention
This invention relates generally to the field of wireless communication. In particular, the invention relates to a reconfigurable mesh network for improved communication system performance in WLAN and other multi-node communication platforms.
Description of the Related Art
Mobile communication systems continue to proliferate worldwide with cellular networks and wireless local area networks (WLAN) providing near ubiquitous coverage. WLAN has been adopted across homes and businesses in most regions of the world, with a large number of client devices such as smartphones, laptops, and tablets capable of WLAN reception. The current focus of IoT (Internet of Things) is to develop products for use in homes and businesses that provide connectivity for control and monitoring, with this connectivity often using WLAN or frequency bands used by WLAN. Some of these IoT in-home applications are critical, such as security monitoring and health monitoring, and require a continuously assessable communication link. More recently WLAN has been adopted for high throughput applications such as video streaming for in-building applications. These types of systems also require good performance from the RF radio and antenna system to ensure quality operation, and these systems increase the number of WLAN systems and RF signaling encountered in businesses, apartment buildings, and neighborhoods. The requirement for increased data rates to support a larger number of users and video applications has been met by a move toward higher orders of modulation in the transmitted signal as well as higher orders of multiple input multiple output (MIMO). These improvements in modulation technique place a requirement on improved signal to noise ratio (SNR) or signal to interference plus noise ratio (SINR) levels. Additionally, better control of the radiated field from the antenna system associated with the access point will be required to provide better communication link quality for an antenna system tasked to provide higher throughput and a more reliable link.
Implementation of mesh network techniques provides a method for improving communication link performance and reliability for networks. A mesh network is a network topology in which each node relays data for the network. All mesh nodes, or a subset of nodes, cooperate in the distribution of data within the network. A mesh network can provide improved reliability and offers redundant links for the portions comprising the network. When one node can no longer operate, the rest of the nodes can still communicate with each other, directly or through one or more intermediate nodes. Wireless mesh networks can self-form and self-heal, with the self-healing feature providing a dynamic method of compensating for faulty devices in a network. Mesh networks can relay messages using either a flooding technique or a routing technique, depending on the protocol and intended application of the communication network.
A rudimentary mesh network topology is one that incorporates repeaters for extending range of the network. Repeater circuits are commonly used in cellular and WLAN communication systems to improve range and to minimize dropped connections due to multi-path. A repeater works by receiving a signal from a communication node and re-transmitting the signal on the same frequency channel or a second frequency channel. With a repeater positioned at a distance from the communication node that represents 75 to 80 percent of the maximum range for communication, and with the repeater utilizing the same transmit power and antenna gain then a near doubling of range can be achieved for an equivalent propagation channel. The area or volume that a communication system provides coverage for can be increased by installing one or multiple repeaters that work in conjunction with the communication node. A wireless repeater circuit does not need a cabled connection to a communication node, easing the installation of repeaters in a communication system.
A mesh network can be used to provide more reliable communication links between nodes in a network, but like a non-mesh network, the communication links are dependent on the performance of the antenna systems on each side of the communication link. Passive antennas, which are typically used in commercial communication systems have fixed radiation patterns and fixed polarization states. Also, for mobile wireless applications such as cellular and WLAN, one end of the communication link can be moving, with this lack of control or knowledge as to location or orientation of the mobile communication device resulting in the need for a broad beamwidth or omni-directional radiation pattern to provide a consistent connection between nodes.